The invention relates to a device for supplying medical instruments with a fluid, in particular a rinsing fluid, which is located in a container which can be set under pressure and into which two cannulas of a differing length may be inserted, wherein a short cannula, via a gas conduit and a release valve, is connectable to a pressurised gas source in order to impinge the container above the fluid level with pressurised gas, whilst the other longer cannula is connectable to a fluid conduit leading to the instrument and protrudes into the fluid located in the container and wherein the fluid flow to the instrument is interruptable with a blocking element and the pressurised gas supply to the container is interruptable with the release valve.
The delivery of fluid such as for example sterilised salt solution to the instrument, is introduced in the manner that a release valve is actuated via a foot switch and then pressurised gas from the pressurised gas source via the release valve impinges the fluid level of the fluid located in the container. The fluid conduit may be blocked or released via a blocking element. If the blocking element is in the release position the fluid on account of the gas pressure acting on it flows across the blocking element to the instrument, which for example comprise optics whose distal lens or distal window, with the fluid exiting from a nozzle, is rinsed free of impurities such as secretion, smoke particles and likewise, at certain time intervals, in order to offer the operator a good viewing through the optics. In order to interrupt the rinsing procedure it is not sufficient to interrupt the pressure supply from the pressurised air source, since the pressure in the container on account of the stored gas volume only sinks slowly and thus the rinsing would continue for a while.
The blocking element is mostly a tubing squeezer into which as a fluid conduit there is applied a flexible tubing, which e.g. is squeezed or released via an electromagnetically actuated pluger, wherein this together with the release valve may be controlled in its function by way of the foot switch.
A disadvantage of these known devices is that several device parts are to be handled and operated differently and separately, such as the connection of the pressurised gas conduit to the pressure source across the release valve to the shorter cannula, furthermore the connection of the fluid conduit to the longer cannula, the insertion of the fluid conduit into the blocking element and the connection to the medical instrument. Furthermore firstly the shorter cannula is to be inserted through a container closure and to be positioned above the fluid level. Subsequently or previously the longer cannula is to be handled similarly but this must be incorporated into the container such that it submerses adequately deeply into the fluid. With all these quite complicated activities also confusions of parts when making the respective connections are not to be ruled out so that there exists a considerable potential risk of error.